Santa Claus, Sponge Bob and San Antonians worked to make spirits bright Saturday on the Museum Reach for the annual River of Lights set to kick off the holiday season.

Holiday vendors, ornament activities, appearances by costumed characters from "Frozen" and a performance by the Brooks Prumo Orchestra, a big band that plays music from the swing era, were also part of the fun.

A 30-foot tree made from LED pixels situated at the the Brooklyn Avenue Lock & Dam was at the celebration's center. The tree was designed by Matt Johnson, whose home light show was featured on ABC’s “The Great Christmas Light Fight.” The tree will continue to activate with a musical light show on the hour from 6 to 9 p.m. throughout the holiday season.

The River of Lights also features multicolored underwater lights and strings of LED lights wrapping lamp posts, trees and handrails along the Museum Reach, which can still be seen each evening.

Jim Kiest contributed to this report.

See who was there to kick off the River of Lights in the photos above.